Calcium incorporation in cultured chondroblasts perturbed by an electromagnetic field

We tested the hypothesis that electric perturbation influences 45Ca incorporation in extracellular matrix (ECM) of cartilage in vitro. Hypertrophic chondroblasts of tibial epiphyses (HC), sternum (SC), and skin fibroblasts (F) were cultured from chick embryos. HC, SC, and F cells were micromass seeded three times per week and maintained at 37.5 degrees C with 5% CO2 for two weeks. Cultures were randomly designated control (C) or exposed (E) to a pulsed electromagnetic field (PEMF). A time course experiment of calcium incorporation for all cultured groups showed that 24 h of exposure produced the largest biological response in chondroblasts. Calcium incorporation required supplemental phosphate. Autoradiography data indicated that the calcium incorporation into macromolecules largely occurred in the ECM. 45Ca steady-state perturbation was enhanced by Streptomyces hyaluronidase (SH) but not by testicular hyaluronidase (TH). 45Ca incorporation experiments tested the effects of phosphate, SH, TH, and PEMF alone and in various combinations on these cultures. Only PEMF or SH plus PEMF with phosphate enhanced 45Ca incorporation. Other experiments examined the effect of rotenone or freeze-thawing on cells exposed to PEMF. PEMF plus freeze-thaw enhanced calcium incorporation in HC only. PEMF appeared to cause disruption of the ECM, enhancing the probability of matrix calcification.     

In vivo measurements of fibrin formation and degradation in nephrotic patients

Summary Intraglomerular fibrin deposition has been implicated as an important pathogenetic mechanism in patients with glomerular diseases and the nephrotic syndrome. To investigate fibrin formation and degradation in nephrosis, we measured fibrinopeptide A by radio-immunoassay and D-dimer by enzyme-linked immunosorbent assay in the plasma of 30 consecutive adult patients with the nephrotic syndrome; in 10 the serum creatinine was more than 2 mg/dl. Both fibrinopeptide A and D-dimer were abnormally elevated in the majority of nephrotics (P<0.001 vs. healthy controls), providing evidence of increased fibrin generation and lysis “in vivo.” A positive correlation was found between fibrinopeptide A and D-dimer (correlation coefficient 0.64,P<0.001), suggesting a close relationship between fibrin formation and degradation. Calcium heparin, administered to 12 nephrotics, caused a marked decrease in plasma fibrinopeptide A, due to a reduction of in vivo thrombin activity. As enhanced thrombin activity can favor fibrin deposition within the renal parenchyma, as well as vascular complications, it is reasonable to assume that an antithrombotic treatment aimed at controlling thrombin generation may ameliorate the natural history of nephrosis.     

The effect of calcium dobesilate on venous function following saphenectomy in coronary artery bypass grafting

BACKGROUND: The aim of this study was to determine whether prophylactic use of calcium dobesilate (CD) can improve venous function after saphenous vein harvest in coronary artery bypass graft (CABG). MATERIALS AND METHODS: A total of 100 patients who underwent elective CABG were divided into four equal groups. In Group A, the greater saphenous vein (GSV) was harvested below the knee and, in Group B, through the knee till the groin. These patients remained untreated. Group C received CD in a dosage of 1500 mg po daily after the GSV was harvested below the knee. Group D received same dosage of CD after the GSV was harvested through the knee till the groin. Venous function of ipsilateral leg was evaluated clinically and by Doppler ultrasonography in the postoperative first week and second month. RESULTS: Clinical findings of venous insufficiency were observed with a similar rate between groups at both early and late periods. In Groups A and B, after 2 months, flow velocities decreased and reflux periods increased significantly. In groups C and D, treatment with CD for 2 months after saphenectomy resulted in a significant increase in flow velocities and a significant decrease in reflux periods. Patients in Groups B and D have significantly more impaired venous functions. CONCLUSION: Saphenectomy results in ipsilateral leg venous dysfunction, which seems to be unrelated to leg swelling and to be more prominent in patients with high-level saphenectomy. In addition, to be careful about the restriction of the saphenectomy procedure into the most appropriate level, prophylactic use of CD can prevent this deterioration when it was added to varice socks.     

钙剂加维生素D治疗对糖尿病患者钙代谢的影响

本文报道NIDDM患者在常规治疗的基础上加用钙剂和维生素D治疗后的钙代谢变化。糖尿病患者单纯用常规治疗控制血糖后,负钙平衡不能完全纠正,而加用钙剂和维生素D治疗后,负钙平衡能完全纠正,并且高于正常对照组平衡值(P<0.01)。说明钙剂加维生素D治疗对糖尿病性骨质疏松是有益的。     

Parvalbumin expression reveals a vibrissa-related pattern in rabbit SI cortex

The expression of parvalbumin-like immunoreactivity (PV-LIR) was examined in the mystacial representation within the primary somatosensory cortex (SI) of postnatal day 21 and adult rabbits. PV-LIR was expressed in a prominent vibrissa-like array of patches in layer IV despite the fact that barrels were indistinct in the cytoarchitecture. Each patch consisted of dense terminal-like PV-LIR and a preferential concentration of intensely labeled stellate neurons. Layer V contained scattered small and large intensely labeled basket cells. Layer Vb had a distinct layer of lightly labeled large pyramidal cells that received labeled basket cell terminations. Upper layer VI also contained patches of terminal-like PV-LIR that were in register with the overlying vibrissae pattern. These patches also contained a preferential distribution of labeled non-pyramidal cells as well as modified pyramidal cells. These results suggest that PV-LIR in rabbits delineates cortical modules composed of thalamorcotical afferents and inhibitory local circuits in the absence of a distinct barrel cytoarchitecure. In contrast, prior studies of rat SI cortex have revealed a distinct barrel cytoarchitecture but a uniform distribution of PV-LIR. The differences in PV-LIR between rodents and lagomorphs within the vibrissae representation in SI may be related to species differences in thalamic and local cortical circuits devoted to the whisker sense.     

腹主动脉灌注丙泊酚减轻脊髓缺血-再灌注损伤与抗氧化和减轻钙超载的关系

目的 本研究拟探讨腹主动脉灌注丙泊酚减轻脊髓缺血-再灌注损伤是否与其抗氧化和减轻钙超载相关.方法 新西兰大耳白兔60只,随机均分为生理盐水(NS)组、10%脂肪乳(P0)组、丙泊酚30mg/kg(P30)组、40mg/kg(P40)组、50mg/kg(P50)组和60mg/kg(P60)组.全麻后开腹阻断肾动脉远端腹主动脉及双侧髂总动脉30min,并从阻断即刻开始,经股动脉预置导管向腹主动脉分别灌注生理盐水、10%脂肪乳及不同剂量的丙泊酚溶液至开放停止.再灌注48h,取L5脊髓节段,检测脊髓组织的超氧化物歧化酶(SOD)活性、丙二醛(MDA)含量和脊髓前角神经细胞内Ca2 荧光强度.结果 与NS和P0组比较,P30、P40、P50和P60组的SOD活性显著升高(P<0.05),MDA含量和Ca2 荧光强度显著降低(P<0.05).SOD活性:P50组最高(P<0.05),P40、P60组高于P30组(P<0.05).MDA含量:P50组最低(P<0.05),P60组低于P30、P40组(P<0.05).Ca2 荧光强度:P60组低于P50组,P50组低于P30、P40组(P<0.05).结论 丙泊酚可剂量依赖性地保护脊髓组织SOD活性、降低MDA含量和脊髓前角神经细胞内Ca2 荧光强度,提示该保护作用与其抗氧化和减轻神经细胞钙超载有关.     

氯胺酮对荷包牡丹碱诱导PC12细胞内Ca2+浓度波动方式的影响

目的研究氯胺酮对荷包牡丹碱诱导PCI2细胞内Ca^2＋浓度波动方式的影响。方法使用含25ng／LNGF的DMED培养基在多聚赖氨酸包被的培养皿中培养PCl2细胞；与终浓度10gmol／L的Ca^2＋指示剂Fluo-3 AM ester共孵育30min洗涤后，加入终浓度50gmol／L荷包牡丹碱；在激光共聚焦显微镜选定多个细胞分别测定荧光强度的变化；随后加入氯胺酮，记录细胞荧光强度的改变。在试验结束前依次加入Triton X-100和EGTA分别记录单个细胞最大荧光强度（Fmax）和最小荧光强度（Fmin），以计算细胞内Ca^2＋的相对强度。结果氯胺酮不改变荷包牡丹碱诱导PCl2细胞内Ca^2＋浓度波动的基线，但抑制细胞内Ca^2＋浓度升高的幅度（P〈0．05），缩短相邻波峰间的时间间隙（P〈0．05）。结论氯胺酮不仅改变荷包牡丹碱诱导PCl2细胞内Ca^2＋浓度升高的幅度，而且改变Ca^2＋浓度波动的周期。     

Distal radial fractures Injectable calcium phosphate bone cement versus conventional treatment

AMEDLINEsearchwasconductedtoidentifystudiespublishedfromJanuary1999toMarch2004thatcom-paredinjectablecalciumphosphatebone(NorianSRS)cementwithconventionaltreatmentindistalradialfrac-tures.Fromalistof13articlesidentifiedfromthesearchstrategy,fourarticleswe…